Table 2.

Antitumor activity of β-glucans from seaweed of the genus Laminaria spp.

Source	Extract	Applicability	Type of Study	Reference
Laminaria digitata	Laminarin	-Dose-dependent induction of cell death -Increase in the percentage of cells in the sub-G1 and G2-M phases -Inhibition of heregulin-stimulated phosphorylation of ErbB2 -Decrease in cellular proliferation	-In vitro (HT-29 colon cancer cells)	[18]
Laminaria japonica	Sulfated polysaccharide fraction (LJSP)	-Highest inhibitory effect on cervical carcinoma U14 cells among five tumor cell lines -In vivo, LJSP inhibited tumor growth and enhanced spleen and thymus indices and bodyweight of U14 tumor-bearing mice -Prominent antitumor activity and low toxic effects	-In vitro (HeLa (cervical carcinoma), U14 (cervical carcinoma), A549 (lung carcinoma), Bel-7402 (hepatoma), and HCT-8 (colon carcinoma) cells) -In vivo (female Kunming mice, 6–8 weeks old; weight, 18–22 g)	[88]
	Novel polysaccharide WPS-2-1	-Dose-dependent antitumor activity against A375 and BGC823 cells -Lower cytotoxic effects on vascular smooth muscle cells	-In vitro (human gastric carcinoma cell line BGC823, human melanoma cell line A375, and aortic vascular smooth muscle cells)	[19]
	Novel polysaccharide WPS-2-1	-Induction of apoptosis associated with alterations in the expression of Bcl-2 family proteins -Mitochondrial apoptotic pathway involvement in WPS-2-1-induced apoptosis, which included the loss of the mitochondrial membrane and activation of caspase-3/9 -Effective inhibition of proliferation of A375 cells in vitro and induction of apoptosis via mitochondrial apoptotic pathway	-In vitro (human melanoma cell line A375)	[90]
	Laminarin polysaccharides (LP1)	-Suppression of apoptotic death around three- or two-fold -Prolonged cell survival in culture at a rate of 20–30%	-In vitro (mouse thymocytes)	[92]